What am I looking at here???

I was going through my smart phone this morning – quickly reviewing the dozens of pics I took during my visit to London. A ghost perhaps? Best answer gets a free signed copy of POLTERGEEKS!

Click on image to enlarge.

So feel free to comment and please leave an email address so that I can pick the best/most plausible answer. Me? I’d like to think it was something supernatural – a fitting end to a trip to promote a book about ghostly activity, witches and slamming evil. (Not that ghosts are evil. Are ghosts evil? You tell me!)